1. Field of the Invention
This invention relates to clocking pulse generators. Accordingly, it is a general object of this invention to provide new and improved generators of such character.
2. Description of the Prior Art
A major purpose of this invention is to provide for a reliable clocking signal for digital applications and for timing applications in an alternating current operating system; for example, the three-phase alternating current sources in commercial and industrial applications or the 110 V alternating current lines in the residential area application. The invention is directed to apparatus for generating a digital clocking pulse directly from a three-phase alternating current electrical power source as well as from a single-phase alternating current line. In a three-phase alternating current electrical power application, the invention is directed to function whenever any single phase among the three phases, any two phases of the three phases, or all three phases of the circuits are energized.
Well known old apparatus for providing clocking pulse generation utilize either crystal controlled oscillators, voltage controlled oscillators, voltage to frequency converters, multivibrators, or timing circuits. Disadvantageously, such prior art circuits require many components including both active devices and passive components. They are expensive; they require well regulated power supplies and/or good temperature compensation.
SUMMARY OF THE INVENTION
Another object of this invention is to provide a new and improved clocking pulse generator which is highly reliable with excellent frequency stability.
Still another object of this invention is to provide for a new and improved clocking pulse generator which requires no temperature compensation so as to minimize any drift due to temperature variations.
Still yet another object of this invention is to provide for a new and improved clocking pulse generator that is cost effective in that only two operational amplifiers with a minimum number of passive components are utilized.
Yet still another object of this invention is to provide for a new and improved electronic clocking pulse generator, applicable for use in a single-phase alternating current line as well as in a three-phase alternating current source.
In accordance with a preferred embodiment of the invention, a clocking pulse generator includes means for receiving voltage from an alternating current electrical power source. A vector summing circuit is coupled to the receiving means for providing a non-zero resultant vector for various conditions of voltage applied to the means. A voltage comparator is coupled to receive the non-zero resultant vector for providing clocking pulses therefrom.
In accordance with another embodiment of the invention, a clocking pulse generator includes means for receiving voltage from a multi-phase alternating current electrical power source. A vector summing circuit, coupled to the receiving means for providing a non-zero resultant vector for any possible combination of multiphase operating conditions, is provided and is coupled to a voltage comparator which provides clocking pulses therefrom.
In accordance with a specific embodiment of the invention, a clocking pulse generator includes means for receiving voltage from a multi-phase alternating current electrical power source. A vector summing circuit provides a non-zero resultant vector for various combinations of the multi-phase operating conditions. A multi-phase voltage dividing circuit couples the receiving means to the vector summing circuit. The non-zero resultant vector is converted into a half-wave rectified signal and is applied to one input of a comparator. The other input of the comparator is coupled to receive a preset threshold voltage. The comparator provides clocking pulses therefrom. In accordance with certain features of the invention, the comparator can include an operational amplifier, and the voltage dividing circuit can include a plurality of transformers.